Switchboard-lamp.



H. D. CURBIER. SWITCHBOARD LAMP.

APPLICATION FILED SEPT. II. 1913.

Patented Oct. 30, 19V/1 'VM MIM@ @QQ-@EU Umm HIRAM SUPPLY COMPANY, or CHICAGO,'rumorsv A CORPORATION or iLLrNoIs.

SWITCHBOARD-LAMP.

Application led September 11, 1913. Serial IO. 789,291.

To all wom it may concern.'

Be it known that I, HIRAM D. Comuna, a

citizen of the United States of America. re

siding at Chicago, in the county of Cook and State of Illinois, have invented certain` new and useful Improvements in Switchboard-Lamps, of which the followingis a specification. l

My invention relates' to switchboard lamps, by which- I mean lamps in general which are small in size and are adapted to be mounted fwithin small confinedv spaces. Lamps of this character are used to a large` extent for 'telephone switchboards where these lamps are mountedin banks, the banks being constructed to' form suitable lamp jacks consisting of springs between which the lamp is held. A suitable opening in front of the lamp `is provided with the opal or crystal through which the light enranates, which crystal or opal may be removed to eXpOse'the lamp. The'lamps, of course, must be frequently withdrawn as they burnout and it has hitherto been eX- tremely ldiiiicult to remove these'lamps sat- 4 isfactorily, and it'has always been aserious difficulty to prevent short circuiting the springs of the lamp jack during the removal operation of the lamp. My invention contemplates means whereby the lamp is so constructedv tliatfshort circuiting of the circuit s prevented and also provides means whereby the insertion or removal. of the lamp is greatly facilitated.

I will explain one form of lamp constructed in accordance with my invention more in detail by "referring to the accompanying drawing in which Figure 1 is a front view of a bank of lamps constructed in accordance vwith my invention;v A

Fig. 2 is a transverse sectional view of the bank, the tool for withdrawing the lamp vbeing also shown;

Fig. 3 is a similar view with the tool shown in position to extract the lamp; and

Fig. 4 is a detail view of the lamp.

The lamp bank consists preferably of a framework 1, upon whose left hand extremity suitable lam supporting springs 2 and 3 are insulating y mounted, being adapted to hold lamps 4. A plurality of these lamp jacks are arranged preferably side by side to f form the bank 5, as shown in Fig. 1. The

lamp bank structure has openings 6 in front Specification of Letters "Patent,v

Patented oet. so, ieri;

be inserted or withdrawn whenever. an Opal 7 is removed. A plate 8 carries the Opalsor crystals I ,which are held -in position in front of each lamp. My improved lamp 4 has on its Opposite sides contact strips 9'and 10, through the `agency of which contact is made with theV springs 2 and 3. The tool 11 which is ordinarily used `to extract lamps, has spring prongs 12#12 projecting therefrom adapted to grasp the lamp between them. These prongs if inserted too far will, as is readily apparent, touch the conducting plates l9 and 10, thus tending to short circuit the springs 2 and 3 which is Objectionable. Inv order to obviate this, and in order to provide a lamp structure which can be easilygrasped by the prongs 12, so that it can be readily removed I arrange the lamp with an annular groove 13 near its outer extremity, which groove serves to form a stop for the bent extremities 14 of the -prongs 12. As will be seen 'more clearly from. Fig. 3, when the tool 11 is inserted the groove 13 will catch' the prongs 14 and pre vent them sfrom being moved farther inwardly, thus to prevent these prongs from v.short cirouiting the conducting plates 9 and 10. This groove 13 at the same time forms readily seen that this particular structure of' the lamp shellv permits the readyremoval of lthe lamp, even though the lamp is tightly grasped between the springs 2 and 3.

Vhile I have illustrated and described my invention in connection with one specific embodiment of the same, yet I do not wish to be limited to .this specic structure as it is apparent many changes may readily suggest themselves. Therefore I desire to cover all such changes as come within the spirit and scope of the appended claims.

Having, however, 'hus'described one form which my invention may take what I claim is new and desire to secure by Letters Patent is:

A lamp of the character described including a cylindrical elongated bulb, a pair of contact strips mounted diametrically opposite each other partially inclosing saidbulb and forming the terminals of the lamp, an annular groove near one extremity of said elongated bulb, said` groove boing posi-A tioned to receive the extendml munded' fingers of a removing implement whereby ille i lamp may be readily inserted into onre-4v moved'from its switch socket, said groove `also preventing the fingers of the removing Signed by me at Chicago, County of Cook i :unl-State of Illinois, in the,p1'esence of two l0 witnesses.` Y i A HIRAM'D: CURRIERL VVitnesses': v 'l Y GEORGE E. MUELLER,

B. OBRIEN. 

